Ole H. Nielsen, PhD

Manager of the computer services group at the Department of Physics at the Technical University of Denmark.
I also work with the Center for Atomic-scale Materials Design (CAMD) at the department.

My professional background is in theoretical solid state physics, primarily electronic structure, total energy and stress calculated within the Density Functional Theory.

I am responsible for the computer and network services at the Department of Physics.

In the summer of 2002 we built a 2.1 TeraFLOPS Linux cluster supercomputer NIFLHEIM out of 480 desktop PCs, which was one of the fastest computers in Europe at the time of installation. From 2012 NIFLHEIM (after several generations of hardware upgrades) has 6200+ CPU cores and 60 TeraFLOPS peak performance, and continues to provide an important infrastructure for the center's research.

Some older scientific papers:

• Solving large nonlinear generalized eigenvalue problems from Density Functional Theory calculations in parallel (abstract, compressed PostScript file of the full paper, 73 kB) (June 1999). Published in Applied Numerical Mathematics Vol. 37 (1-2) (2001) pp. 189-199; The paper is available on-line.
• Performance Evaluation and Modeling of Reduction Operations on the IBM RS/6000 SP Parallel Computer (abstract, compressed PostScript file of the full paper, 157 kB). Proceedings of Workshop on Applied Parallel Computing in Industrial Problems and Optimization (PARA96), ed. J. Wasniewski, Springer Lecture Notes in Computer Science, vol. 1184, p. 272 (1996).
• Data-parallel molecular dynamics with neighbor-lists. (PostScript file 45 kB). Proceedings of Workshop on Applied Parallel Computing in Physics, Chemistry and Engineering Science (PARA95), ed. J. Wasniewski, Springer Lecture Notes in Computer Science, vol. 1041, p. 443 (1995).
• Parallel ab-initio molecular dynamics. (PostScript file 49 kB) (1995)
generation of dislocations. (1995)
• Melting a copper cluster: Critical droplet theory. (1994)
• Stress theorem in the determination of static equilibrium by the density functional method by P Gomes Dacosta, O H Nielsen and K Kunc, J. Phys. C: Solid State Phys. 19 316 (1986).
• Optical phonons and elasticity of diamond at Megabar stresses by O. H. Nielsen, Physical Review B 34, 5808-5819 (1986).
• Quantum-mechanical theory of stress and force by O. H. Nielsen and Richard M. Martin, Physical Review B 32, 3780-3791 (1985).
• Stresses in semiconductors: Ab initio calculations on Si, Ge, and GaAs by O. H. Nielsen and Richard M. Martin, Physical Review B 32, 3792-3805 (1985).
• First-Principles Calculation of Stress by O. H. Nielsen and Richard M. Martin, Physical Review Letters 50, 697 (1983).
• Lattice dynamics of substitutional 119m-Sn in silicon, germanium, and alpha-tin using an adiabatic bond-charge model by O. H. Nielsen, Physical Review B 25, 1225 (1982).

You can send me E-mail at the address Ole.H.Nielsen (at) fysik.dtu.dk.

Check the Center for Atomic-scale Materials Design (CAMD) for more information about our activities.

Miscellaneous:

• math jokes.
• Generel Lektorteori.

Address:
Dr. Ole Holm Nielsen
Department of Physics
Technical University of Denmark
Building 307
DK-2800 Kongens Lyngby
Denmark

E-mail: Ole.H.Nielsen \at/ fysik.dtu.dk
Telephone: (+45) 4525 3187.
Fax: (+45) 4593 2399.
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